The role of transverse speed on deposition height and material efficiency in laser deposited titanium alloy
- Mahamood, Rasheedat M., Akinlabi, Esther Titilayo, Shukla, Mukul, Pityana, Sisa
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2013
- Subjects: Additive manufacturing , Laser metal deposition , Material efficiency , Titanium alloy
- Type: Article
- Identifier: uj:4895 , http://hdl.handle.net/10210/12609
- Description: The most commonly used aerospace titanium alloy, Ti6Al4V, was deposited on Ti6Al4V plate of dimension 72 x 72 x5mm. The laser power of 3 kW, powder flow rate of 1.44 g/min and gas flow rate of 4 l/min were used throughout the deposition process. The transverse/ scanning speed was varied between 0.005 to 0.095 m/sec according to established result of the preliminary study that produces full dense and pore free deposits. The mass of the deposited powder was obtained by weight the substrate before deposition and reweighing after deposition. The substrate and the deposits were thoroughly cleaned using wire brush and acetone to remove unmelted powder particles from the surface of the substrate and the deposit. The height and width of the deposits were measured with Venier Caliper and the material efficiencies were determined using developed equations. The effect of the scanning speed on the material efficiency and deposit height were extensively studied and the results showed that for the set of processing parameter used in this study the optimum scanning speed is approximately 0.045 m/sec.
- Full Text:
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2013
- Subjects: Additive manufacturing , Laser metal deposition , Material efficiency , Titanium alloy
- Type: Article
- Identifier: uj:4895 , http://hdl.handle.net/10210/12609
- Description: The most commonly used aerospace titanium alloy, Ti6Al4V, was deposited on Ti6Al4V plate of dimension 72 x 72 x5mm. The laser power of 3 kW, powder flow rate of 1.44 g/min and gas flow rate of 4 l/min were used throughout the deposition process. The transverse/ scanning speed was varied between 0.005 to 0.095 m/sec according to established result of the preliminary study that produces full dense and pore free deposits. The mass of the deposited powder was obtained by weight the substrate before deposition and reweighing after deposition. The substrate and the deposits were thoroughly cleaned using wire brush and acetone to remove unmelted powder particles from the surface of the substrate and the deposit. The height and width of the deposits were measured with Venier Caliper and the material efficiencies were determined using developed equations. The effect of the scanning speed on the material efficiency and deposit height were extensively studied and the results showed that for the set of processing parameter used in this study the optimum scanning speed is approximately 0.045 m/sec.
- Full Text:
Tensile properties of long untreated and alkali treated Napier grass fiber strands/epoxy composites
- Kommula, Venkata Parasuram, Kanchireddy, Obi Reddy, Shukla, Mukul, Marwala, Tshilidzi
- Authors: Kommula, Venkata Parasuram , Kanchireddy, Obi Reddy , Shukla, Mukul , Marwala, Tshilidzi
- Date: 2013
- Subjects: Tensile strength , Alkali treatment , Napier Grass fibers
- Type: Article
- Identifier: uj:4856 , http://hdl.handle.net/10210/12532
- Description: Napier grass fiber strands were extracted using the combined mechanical and water retting process. The extracted fiber strands were treated with various proportions (5, 10 and 15% w/v) of NaOH solution to improve their surface morphology and bonding with the resin. This study investigates the Tensile properties of composites made by reinforcing alkali treated, long Napier grass fiber strands in to epoxy resin with different orientations (0º). The composites were prepared with 0, 5, 10, and 15% of alkali treatment and with a fiber loading (weight %) of 10, 20, and 30%. The effect of alkali treatment, orientation and fiber loading on the tensile strength of the composites was analyzed using universal testing machine. Quantitative results from this study will be useful for more accurate design of Napier grass fiber strand reinforced composite materials for possible automotive applications.
- Full Text:
- Authors: Kommula, Venkata Parasuram , Kanchireddy, Obi Reddy , Shukla, Mukul , Marwala, Tshilidzi
- Date: 2013
- Subjects: Tensile strength , Alkali treatment , Napier Grass fibers
- Type: Article
- Identifier: uj:4856 , http://hdl.handle.net/10210/12532
- Description: Napier grass fiber strands were extracted using the combined mechanical and water retting process. The extracted fiber strands were treated with various proportions (5, 10 and 15% w/v) of NaOH solution to improve their surface morphology and bonding with the resin. This study investigates the Tensile properties of composites made by reinforcing alkali treated, long Napier grass fiber strands in to epoxy resin with different orientations (0º). The composites were prepared with 0, 5, 10, and 15% of alkali treatment and with a fiber loading (weight %) of 10, 20, and 30%. The effect of alkali treatment, orientation and fiber loading on the tensile strength of the composites was analyzed using universal testing machine. Quantitative results from this study will be useful for more accurate design of Napier grass fiber strand reinforced composite materials for possible automotive applications.
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Pyrolitic tyre derived fuel : a review
- Pilusa, Jefrey T., Shukla, Mukul, Muzenda, Edison
- Authors: Pilusa, Jefrey T. , Shukla, Mukul , Muzenda, Edison
- Date: 2013
- Subjects: Alternative fuel , Waste tyre pyrolysis , Waste tyre utilization
- Type: Article
- Identifier: uj:4859 , http://hdl.handle.net/10210/12535
- Description: This paper reviews the potential of using waste tyre pyrolitic fuel as an alternative energy taking into account its environmental impact and national regulations. The properties of tyre derived oil and its derivatives were evaluated as a potential alternative low cost fuel for various industrial applications. The benefit of pyrolysis versus landfill disposal of waste tyres while producing low cost fuel and other value add products remains a driving force for this initiative. The downstream challenges associated with combustion of high sulphur bearing fuels such as tyre pyrolitic fuels calls for more research to into purification and refining of these fuels. Environmental Legislations on permitting the fuel production facilities, blending of the fuel derivatives with existing commercial diesel need to be clearly defined and facilitated accordingly.
- Full Text:
- Authors: Pilusa, Jefrey T. , Shukla, Mukul , Muzenda, Edison
- Date: 2013
- Subjects: Alternative fuel , Waste tyre pyrolysis , Waste tyre utilization
- Type: Article
- Identifier: uj:4859 , http://hdl.handle.net/10210/12535
- Description: This paper reviews the potential of using waste tyre pyrolitic fuel as an alternative energy taking into account its environmental impact and national regulations. The properties of tyre derived oil and its derivatives were evaluated as a potential alternative low cost fuel for various industrial applications. The benefit of pyrolysis versus landfill disposal of waste tyres while producing low cost fuel and other value add products remains a driving force for this initiative. The downstream challenges associated with combustion of high sulphur bearing fuels such as tyre pyrolitic fuels calls for more research to into purification and refining of these fuels. Environmental Legislations on permitting the fuel production facilities, blending of the fuel derivatives with existing commercial diesel need to be clearly defined and facilitated accordingly.
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Molecular filtration of rubber derived fuel
- Pilusa, Jefrey, Muzenda, Edison, Shukla, Mukul
- Authors: Pilusa, Jefrey , Muzenda, Edison , Shukla, Mukul
- Date: 2013
- Subjects: Pyrolysis fuel , Waste-to-energy , Rubber derived fuel
- Type: Article
- Identifier: uj:4965 , http://hdl.handle.net/10210/13066
- Description: The work presented in this article reviews the possible methods for removal of mercaptans from distilled rubber derived fuel. Distilled rubber derived fuel is a potential additive for diesel fuel; therefore reduction of sulphur compounds in this fuel is essential for application in compression ignition engines. Membrane filtration of distilled rubber fuel using 13-X molecular sieves has shown a significant reduction in sulphur content. It was observed that distilled rubber fuel can be effectively filtered via single pass to remove up to 53.67% of the fuel’s initial sulphur.
- Full Text:
- Authors: Pilusa, Jefrey , Muzenda, Edison , Shukla, Mukul
- Date: 2013
- Subjects: Pyrolysis fuel , Waste-to-energy , Rubber derived fuel
- Type: Article
- Identifier: uj:4965 , http://hdl.handle.net/10210/13066
- Description: The work presented in this article reviews the possible methods for removal of mercaptans from distilled rubber derived fuel. Distilled rubber derived fuel is a potential additive for diesel fuel; therefore reduction of sulphur compounds in this fuel is essential for application in compression ignition engines. Membrane filtration of distilled rubber fuel using 13-X molecular sieves has shown a significant reduction in sulphur content. It was observed that distilled rubber fuel can be effectively filtered via single pass to remove up to 53.67% of the fuel’s initial sulphur.
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Microstructures, hardness and bioactivity of hydroxyapatite coatings deposited by direct laser melting process
- Tlotleng, Monnamme, Akinlabi, Esther Titilayo, Shukla, Mukul, Pityana, Sisa
- Authors: Tlotleng, Monnamme , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2014
- Subjects: Direct laser melting , Laser power , Hydroxyapatite coatings
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/376152 , uj:4994 , http://hdl.handle.net/10210/13129
- Description: Hydroxyapatite (HAP) coatings on bioinert metals such as Ti–6Al–4V are necessary for biomedical applications. Together, HAP and Ti–6Al–4V are biocompatible and bioactive. The challenges of depositing HAP on Ti–6Al–4V with traditional thermal spraying techniques are well founded. In this paper, HAP was coated on Ti–6Al–4V using direct laser melting (DLM) process. This process, unlike the traditional coating processes, is able to achieve coatings with good metallurgical bonding and little dilution. The microstructural and mechanical properties, chemical composition and bio-activities of the produced coatings were studied with optical microscopy, scanning electron microscope equipped with energy dispersive X-ray spectroscopy, and Vickers hardness machine, and by immersion test in Hanks' solution. The results showed that the choice of the laser power has much influence on the evolving microstructure, the mechanical properties and the retainment of HAP on the surface of the coating. Also, the choice of laser power of 750Wled to no dilution. The microhardness results inferred a strong intermetallic– ceramic interfacial bonding; which meant that the 750 W coating could survive long in service. Also, the coating was softer at the surface and stronger in the heat affected zones. Hence, this process parameter setting can be considered as an optimal setting. The soak tests revealed that the surface of the coating had unmelted crystals of HAP. The CaP ratio conducted on the soaked coating was 2.00 which corresponded to tetra calcium phosphate. This coating seems attractive for metallic implant applications.
- Full Text:
- Authors: Tlotleng, Monnamme , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2014
- Subjects: Direct laser melting , Laser power , Hydroxyapatite coatings
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/376152 , uj:4994 , http://hdl.handle.net/10210/13129
- Description: Hydroxyapatite (HAP) coatings on bioinert metals such as Ti–6Al–4V are necessary for biomedical applications. Together, HAP and Ti–6Al–4V are biocompatible and bioactive. The challenges of depositing HAP on Ti–6Al–4V with traditional thermal spraying techniques are well founded. In this paper, HAP was coated on Ti–6Al–4V using direct laser melting (DLM) process. This process, unlike the traditional coating processes, is able to achieve coatings with good metallurgical bonding and little dilution. The microstructural and mechanical properties, chemical composition and bio-activities of the produced coatings were studied with optical microscopy, scanning electron microscope equipped with energy dispersive X-ray spectroscopy, and Vickers hardness machine, and by immersion test in Hanks' solution. The results showed that the choice of the laser power has much influence on the evolving microstructure, the mechanical properties and the retainment of HAP on the surface of the coating. Also, the choice of laser power of 750Wled to no dilution. The microhardness results inferred a strong intermetallic– ceramic interfacial bonding; which meant that the 750 W coating could survive long in service. Also, the coating was softer at the surface and stronger in the heat affected zones. Hence, this process parameter setting can be considered as an optimal setting. The soak tests revealed that the surface of the coating had unmelted crystals of HAP. The CaP ratio conducted on the soaked coating was 2.00 which corresponded to tetra calcium phosphate. This coating seems attractive for metallic implant applications.
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Microstructural and mechanical evaluation of laser-assisted cold sprayed bio-ceramic coatings : potential use for biomedical applications
- Tlotleng, Monnamme, Akinlabi, Esther Titilayo, Shukla, Mukul, Pityana, Sisa
- Authors: Tlotleng, Monnamme , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2014
- Subjects: Titanium , Laser power , Cold spray , Laser-assisted cold spray , Hydroxyapatite
- Type: Article
- Identifier: uj:5135 , ISSN 1544-1016 , http://hdl.handle.net/10210/14101
- Description: Bio-composite coatings of 20 wt.%, HAP and 80 wt.%, HAP were synthesized on Ti-6Al-4V substrates using LACS technique. The coatings were produced with a laser power of 2.5 kW, powder-laser spot trailing by 5 s. The coatings were analyzed for the microstructures, microhardness, composition, and bio-corrosion using SEM-EDS, XRD, hardness tester, and Metrohm PGSTAT101 machine. SEM images indicated least pores and crack-free coating with dark-spots of Ti-HAP for the 20 wt.%, HAP as opposed to the 80 wt.%, HAP coating which was solid, porous and finely cracked and had semi-melted Ti-HAP particles. The EDS mappings showed high content of HAP for the 80 wt.%, HAP coating. The diffraction patterns were similar, even though the Ti-HAP peak was broader in the 80 wt.%, HAP coating and the HAP intensities were lower for this coating except for the (004) peak. The hardness values taken at the interface inferred that the 80 wt.%, HAP coating was least bonded. It was possible to conclude that when this phase material increased the hardness dropped considerably. The bio-corrosion tests indicated that the presence of HAP in coating leads to a kinetically active coating as opposed to pure titanium coating.
- Full Text:
- Authors: Tlotleng, Monnamme , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2014
- Subjects: Titanium , Laser power , Cold spray , Laser-assisted cold spray , Hydroxyapatite
- Type: Article
- Identifier: uj:5135 , ISSN 1544-1016 , http://hdl.handle.net/10210/14101
- Description: Bio-composite coatings of 20 wt.%, HAP and 80 wt.%, HAP were synthesized on Ti-6Al-4V substrates using LACS technique. The coatings were produced with a laser power of 2.5 kW, powder-laser spot trailing by 5 s. The coatings were analyzed for the microstructures, microhardness, composition, and bio-corrosion using SEM-EDS, XRD, hardness tester, and Metrohm PGSTAT101 machine. SEM images indicated least pores and crack-free coating with dark-spots of Ti-HAP for the 20 wt.%, HAP as opposed to the 80 wt.%, HAP coating which was solid, porous and finely cracked and had semi-melted Ti-HAP particles. The EDS mappings showed high content of HAP for the 80 wt.%, HAP coating. The diffraction patterns were similar, even though the Ti-HAP peak was broader in the 80 wt.%, HAP coating and the HAP intensities were lower for this coating except for the (004) peak. The hardness values taken at the interface inferred that the 80 wt.%, HAP coating was least bonded. It was possible to conclude that when this phase material increased the hardness dropped considerably. The bio-corrosion tests indicated that the presence of HAP in coating leads to a kinetically active coating as opposed to pure titanium coating.
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Laser metal deposition of Ti6Al4V : a study on the effect of laser power on microstructure and microhardness
- Mahamood, Rasheedat M., Akinlabi, Esther Titilayo, Shukla, Mukul, Pityana, Sisa
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2013
- Subjects: Laser metal deposition process , Laser power , Ti6Al4V , Macroscopic banding , Microhardness , Microstructure
- Type: Article
- Identifier: uj:4896 , http://hdl.handle.net/10210/12610
- Description: The effect of laser power on the resulting microstructure and microhardness of laser metal deposited Ti6Al4V powder on Ti6Al4V substrate has been investigated. The tracks were deposited using 99.6 % pure Ti6Al4V powder of particle size ranging between 150 - 200 μm on 99.6% Ti6Al4V substrate. The laser power was varied between 0.8 - 3.0 kW while the scanning speed, powder flow rate and the gas flow rate were kept at the values of 0.005 m/sec, 1.44 g/min and 4 l /min respectively. The microstructure and the microhardness were studied using the optical microscope and the Vickers hardness tester respectively. Layer band or macroscopic banding was observed in all the samples which is phenomenon as it was only reported in the literature for multi-layer deposits. The literature attributed re-melting of the previous layers by the succeeding layers as being responsible for their formation. This study has revealed that this band could be as a result of shrinkage happening in the fusion zone as a result of the interaction of the deposited powder and the melt pool created by the substrate material. This study also reveals the relationship between the microstructure, the average microhardness and the laser power which are comprehensively discussed. The higher the laser power, the lower the density of columnar prior beta grain structure. Also the average microhardness increases as the laser power increases.
- Full Text:
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2013
- Subjects: Laser metal deposition process , Laser power , Ti6Al4V , Macroscopic banding , Microhardness , Microstructure
- Type: Article
- Identifier: uj:4896 , http://hdl.handle.net/10210/12610
- Description: The effect of laser power on the resulting microstructure and microhardness of laser metal deposited Ti6Al4V powder on Ti6Al4V substrate has been investigated. The tracks were deposited using 99.6 % pure Ti6Al4V powder of particle size ranging between 150 - 200 μm on 99.6% Ti6Al4V substrate. The laser power was varied between 0.8 - 3.0 kW while the scanning speed, powder flow rate and the gas flow rate were kept at the values of 0.005 m/sec, 1.44 g/min and 4 l /min respectively. The microstructure and the microhardness were studied using the optical microscope and the Vickers hardness tester respectively. Layer band or macroscopic banding was observed in all the samples which is phenomenon as it was only reported in the literature for multi-layer deposits. The literature attributed re-melting of the previous layers by the succeeding layers as being responsible for their formation. This study has revealed that this band could be as a result of shrinkage happening in the fusion zone as a result of the interaction of the deposited powder and the melt pool created by the substrate material. This study also reveals the relationship between the microstructure, the average microhardness and the laser power which are comprehensively discussed. The higher the laser power, the lower the density of columnar prior beta grain structure. Also the average microhardness increases as the laser power increases.
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Laser forming of titanium and its alloys – an overview
- Akinlabi, Esther Titilayo, Shukla, Mukul, Akinlabi, Stephen A.
- Authors: Akinlabi, Esther Titilayo , Shukla, Mukul , Akinlabi, Stephen A.
- Date: 2012
- Subjects: Titanium , Titanium alloy , Laser beam forming
- Type: Article
- Identifier: uj:5334 , ISSN 2070-3740 , http://hdl.handle.net/10210/8877
- Description: Laser beam forming is a novel technique developed for the joining of metallic components. In this study, an overview of the laser beam forming process, areas of application, the basic mechanisms of the laser beam forming process, some recent research studies and the need to focus more research effort on improving the laser-material interaction of laser beam forming of titanium and its alloys are presented.
- Full Text:
- Authors: Akinlabi, Esther Titilayo , Shukla, Mukul , Akinlabi, Stephen A.
- Date: 2012
- Subjects: Titanium , Titanium alloy , Laser beam forming
- Type: Article
- Identifier: uj:5334 , ISSN 2070-3740 , http://hdl.handle.net/10210/8877
- Description: Laser beam forming is a novel technique developed for the joining of metallic components. In this study, an overview of the laser beam forming process, areas of application, the basic mechanisms of the laser beam forming process, some recent research studies and the need to focus more research effort on improving the laser-material interaction of laser beam forming of titanium and its alloys are presented.
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Laser beam forming of 3 mm steel plate and the evolving properties
- Akinlabi, Stephen, Shukla, Mukul, Akinlabi, Esther Titilayo, Tshilidzi, Marwala
- Authors: Akinlabi, Stephen , Shukla, Mukul , Akinlabi, Esther Titilayo , Tshilidzi, Marwala
- Date: 2011
- Subjects: Laser beam forming , Deformation , Elongated grains
- Type: Article
- Identifier: uj:5325 , ISSN 1307-6884 , http://hdl.handle.net/10210/8239
- Description: This paper reports the evolving properties of a 3 mm low carbon steel plate after Laser Beam Forming process (LBF) To achieve this objective, the chemical analyse material and the formed components were carried out and compared; thereafter both were characterized through microhardness profiling, microstructural evaluation and tensile testing. The chemical analyses showed an increase in the elemental concentration of the formed component when compared to the as received material; this can be attributed to the enhancement property of the LBF process. The Ultimate Tensile Strength (UTS) and the Vickers microhardness of the formed component shows an increase when compared to the as received material, this was attributed to strain hardening and grain refinement brought about by the LBF process. The microstructure of the as received steel consists of equiaxed ferrit and pearlite while that of the formed component exhibits elongated grains.
- Full Text:
- Authors: Akinlabi, Stephen , Shukla, Mukul , Akinlabi, Esther Titilayo , Tshilidzi, Marwala
- Date: 2011
- Subjects: Laser beam forming , Deformation , Elongated grains
- Type: Article
- Identifier: uj:5325 , ISSN 1307-6884 , http://hdl.handle.net/10210/8239
- Description: This paper reports the evolving properties of a 3 mm low carbon steel plate after Laser Beam Forming process (LBF) To achieve this objective, the chemical analyse material and the formed components were carried out and compared; thereafter both were characterized through microhardness profiling, microstructural evaluation and tensile testing. The chemical analyses showed an increase in the elemental concentration of the formed component when compared to the as received material; this can be attributed to the enhancement property of the LBF process. The Ultimate Tensile Strength (UTS) and the Vickers microhardness of the formed component shows an increase when compared to the as received material, this was attributed to strain hardening and grain refinement brought about by the LBF process. The microstructure of the as received steel consists of equiaxed ferrit and pearlite while that of the formed component exhibits elongated grains.
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Investigation of single pass filtration of tyre derived fuel-diesel blend
- Pilusa, Jefrey T., Muzenda, Edison, Shukla, Mukul
- Authors: Pilusa, Jefrey T. , Muzenda, Edison , Shukla, Mukul
- Date: 2013
- Subjects: Waste tyre pyrolysis , Tyre derived fuel , Single pass filtration
- Type: Article
- Identifier: uj:4893 , http://hdl.handle.net/10210/12607
- Description: This research reports the experimental investigation of single pass filtration of tyre derived fuel and low sulphur diesel blend using a bench scale two stage micro-molecular filtration set-up. Crude tyre pyrolitic oil obtained from slow pyrolysis of waste tyres was distillated at 250ºC to recover the light to medium fraction from the oil. The distillate was characterized and blended with low sulphur diesel at a volume ratio of 1.5:1 for bench scale filtration tests. Optimum packing densities for both micro and molecular filter media were determined followed by single pass filtration to evaluate the contaminants removal efficiencies. It was observed that the selected packing density of 168kg/m3 and pattern for micro filter medium can remove up to 2.5μm particle size in the fuel. The 18% reduction in total sulphur in the fuel after filtration was an indication of liquid phase mass transfer (molecular filtration) on the active surface of the molecular sieves.
- Full Text:
- Authors: Pilusa, Jefrey T. , Muzenda, Edison , Shukla, Mukul
- Date: 2013
- Subjects: Waste tyre pyrolysis , Tyre derived fuel , Single pass filtration
- Type: Article
- Identifier: uj:4893 , http://hdl.handle.net/10210/12607
- Description: This research reports the experimental investigation of single pass filtration of tyre derived fuel and low sulphur diesel blend using a bench scale two stage micro-molecular filtration set-up. Crude tyre pyrolitic oil obtained from slow pyrolysis of waste tyres was distillated at 250ºC to recover the light to medium fraction from the oil. The distillate was characterized and blended with low sulphur diesel at a volume ratio of 1.5:1 for bench scale filtration tests. Optimum packing densities for both micro and molecular filter media were determined followed by single pass filtration to evaluate the contaminants removal efficiencies. It was observed that the selected packing density of 168kg/m3 and pattern for micro filter medium can remove up to 2.5μm particle size in the fuel. The 18% reduction in total sulphur in the fuel after filtration was an indication of liquid phase mass transfer (molecular filtration) on the active surface of the molecular sieves.
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Gas flow rate and powder flow rate effect on properties of laser metal deposited Ti6Al4V
- Pityana, Sisa, Mahamood, Rasheedat M., Akinlabi, Esther Titilayo, Shukla, Mukul
- Authors: Pityana, Sisa , Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul
- Date: 2013
- Subjects: Gas flow rate , Microhardness , Microstructure , Powder flow rate , Laser metal deposition , Additive manufacturing technology
- Type: Article
- Identifier: uj:4849 , http://hdl.handle.net/10210/12516
- Description: Tracks of Ti6Al4V powder were deposited on Ti6Al4V substrate using Laser Metal Deposition (LMD) process, an Additive Manufacturing (AM) manufacturing technology, at a laser power and scanning speed maintained at 1.8 kW and 0.005 m/s respectively. The powder flow rate and the gas flow rate were varied to study their effect on the physical, metallurgical and mechanical properties of the deposits. The physical properties studied are: the track width, the track height and the deposit weight. The mechanical property studied is the Microhardness profiling using Microhardness indenter at a load of 500g and dwelling time of 15 μm. The metallurgical property studied is the microstructure using the Optical microscopy. This study revealed that as the powder flow rate was increased, the track width, track height and the deposit weight were increased while as the powder flow rate was increased, the track width, track height and the deposit weight decreased. The results are presented and discussed in detail.
- Full Text:
- Authors: Pityana, Sisa , Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul
- Date: 2013
- Subjects: Gas flow rate , Microhardness , Microstructure , Powder flow rate , Laser metal deposition , Additive manufacturing technology
- Type: Article
- Identifier: uj:4849 , http://hdl.handle.net/10210/12516
- Description: Tracks of Ti6Al4V powder were deposited on Ti6Al4V substrate using Laser Metal Deposition (LMD) process, an Additive Manufacturing (AM) manufacturing technology, at a laser power and scanning speed maintained at 1.8 kW and 0.005 m/s respectively. The powder flow rate and the gas flow rate were varied to study their effect on the physical, metallurgical and mechanical properties of the deposits. The physical properties studied are: the track width, the track height and the deposit weight. The mechanical property studied is the Microhardness profiling using Microhardness indenter at a load of 500g and dwelling time of 15 μm. The metallurgical property studied is the microstructure using the Optical microscopy. This study revealed that as the powder flow rate was increased, the track width, track height and the deposit weight were increased while as the powder flow rate was increased, the track width, track height and the deposit weight decreased. The results are presented and discussed in detail.
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Functionally graded material: an overview
- Mahamood, Rasheedat M., Akinlabi, Esther Titilayo, Shukla, Mukul, Pityana, Sisa
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2012
- Subjects: Functionally graded material
- Type: Article
- Identifier: uj:5342 , ISSN 978-988-19252-2-0 , http://hdl.handle.net/10210/9887
- Description: Functionally Graded Material (FGM) belongs to a class of advanced material characterized by variation in properties as the dimension varies. The overall properties of FMG are unique and different from any of the individual material that forms it. There is a wide range of applications for FGM and it is expected to increase as the cost of material processing and fabrication processes are reduced by improving these processes. In this study, an overview of fabrication processes, area of application, some recent research studies and the need to focus more research effort on improving the most promising FGM fabrication method (solid freeform SFF) is presented. Improving the performance of SFF processes and extensive studies on material characterization on components produced will go a long way in bringing down the manufacturing cost of FGM and increase productivity in this regard.
- Full Text:
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2012
- Subjects: Functionally graded material
- Type: Article
- Identifier: uj:5342 , ISSN 978-988-19252-2-0 , http://hdl.handle.net/10210/9887
- Description: Functionally Graded Material (FGM) belongs to a class of advanced material characterized by variation in properties as the dimension varies. The overall properties of FMG are unique and different from any of the individual material that forms it. There is a wide range of applications for FGM and it is expected to increase as the cost of material processing and fabrication processes are reduced by improving these processes. In this study, an overview of fabrication processes, area of application, some recent research studies and the need to focus more research effort on improving the most promising FGM fabrication method (solid freeform SFF) is presented. Improving the performance of SFF processes and extensive studies on material characterization on components produced will go a long way in bringing down the manufacturing cost of FGM and increase productivity in this regard.
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Effect of scanning speed on material efficiency of laser metal deposited Ti6Al4V
- Akinlabi, Esther Titilayo, Mahamood, Rasheedat M., Shukla, Mukul, Pityana, Sisa
- Authors: Akinlabi, Esther Titilayo , Mahamood, Rasheedat M. , Shukla, Mukul , Pityana, Sisa
- Date: 2012
- Subjects: Laser Metal Deposition Process , Material efficiency , Titanium alloy , Laser scanning speed
- Type: Article
- Identifier: uj:5337 , ISSN 2010-3778 , http://hdl.handle.net/10210/8880
- Description: The study of effect of laser scanning speed on material efficiency in Ti6Al4V application is very important because unspent powder is not reusable because of high temperature oxygen pick-up and contamination. This study carried out an extensive study on the effect of scanning speed on material efficiency by varying the speed between 0.01 to 0.1m/sec. The samples are wire brushed and cleaned with acetone after each deposition to remove un-melted particles from the surface of the deposit. The substrate is weighed before and after deposition. A formula was developed to calculate the material efficiency and the scanning speed was compared with the powder efficiency obtained. The results are presented and discussed. The study revealed that the optimum scanning speed exists for this study at 0.01m/sec, above and below which the powder efficiency will drop.
- Full Text:
- Authors: Akinlabi, Esther Titilayo , Mahamood, Rasheedat M. , Shukla, Mukul , Pityana, Sisa
- Date: 2012
- Subjects: Laser Metal Deposition Process , Material efficiency , Titanium alloy , Laser scanning speed
- Type: Article
- Identifier: uj:5337 , ISSN 2010-3778 , http://hdl.handle.net/10210/8880
- Description: The study of effect of laser scanning speed on material efficiency in Ti6Al4V application is very important because unspent powder is not reusable because of high temperature oxygen pick-up and contamination. This study carried out an extensive study on the effect of scanning speed on material efficiency by varying the speed between 0.01 to 0.1m/sec. The samples are wire brushed and cleaned with acetone after each deposition to remove un-melted particles from the surface of the deposit. The substrate is weighed before and after deposition. A formula was developed to calculate the material efficiency and the scanning speed was compared with the powder efficiency obtained. The results are presented and discussed. The study revealed that the optimum scanning speed exists for this study at 0.01m/sec, above and below which the powder efficiency will drop.
- Full Text:
Effect of in-line post diesel filtration on engine exhaust emissions and fuel consumption
- Pilusa, Jefrey, Muzenda, Edison, Shukla, Mukul
- Authors: Pilusa, Jefrey , Muzenda, Edison , Shukla, Mukul
- Date: 2013
- Subjects: Compression ignition , Diesel injectors , Engine performance , Fuel filtration , Internal combustion
- Type: Article
- Identifier: uj:4841 , http://hdl.handle.net/10210/12489
- Description: The work presented in this article investigated the effect of a Whale diesel filter on engine’s exhaust emissions, fuel consumption and performance. A stationary ADE 407T heavy duty diesel engine coupled to a hydraulic dynamometer was used to investigate the performance, fuel efficiency and emissions tests under controlled conditions in a laboratory.
- Full Text:
- Authors: Pilusa, Jefrey , Muzenda, Edison , Shukla, Mukul
- Date: 2013
- Subjects: Compression ignition , Diesel injectors , Engine performance , Fuel filtration , Internal combustion
- Type: Article
- Identifier: uj:4841 , http://hdl.handle.net/10210/12489
- Description: The work presented in this article investigated the effect of a Whale diesel filter on engine’s exhaust emissions, fuel consumption and performance. A stationary ADE 407T heavy duty diesel engine coupled to a hydraulic dynamometer was used to investigate the performance, fuel efficiency and emissions tests under controlled conditions in a laboratory.
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Economic assessment of waste tyres pyrolysis technology: a case study for Gauteng Province, South Africa
- Pilusa, Jefrey, Shukla, Mukul, Muzenda, Edison
- Authors: Pilusa, Jefrey , Shukla, Mukul , Muzenda, Edison
- Date: 2014
- Subjects: Waste tyres - South Africa - Gauteng , Waste tyre pyrolysis - South Africa - Gauteng
- Type: Article
- Identifier: uj:4905 , ISSN 2349-1442 , http://hdl.handle.net/10210/13004
- Description: This study evaluates the viability of pyrolysis technology as a treatment process for waste tyres with the aim of producing alternative fuel and other high value products. A financial model was formulated to evaluate the economic feasibility of this technology as an alternative disposal method. It was discovered that pyrolysis technology becomes more viable when there is guaranteed product off-takes at a given price. Further processing of the crude tyre oil and carbon black is important for production of consistent quality products. Gauteng province alone will require a capital injection of US $59.8 million to setup 14 waste tyres pyrolysis treatment facilities to treat 134,922 tons per annum of waste tyres with a potential investment return and gross margin of 29.79% and 34.59%, respectively. These facilities can produce up to 46.8 million litres per annum of refined tyre derived fuel at cost of $ 0.516/litre and other secondary value add products for local and export markets.
- Full Text:
- Authors: Pilusa, Jefrey , Shukla, Mukul , Muzenda, Edison
- Date: 2014
- Subjects: Waste tyres - South Africa - Gauteng , Waste tyre pyrolysis - South Africa - Gauteng
- Type: Article
- Identifier: uj:4905 , ISSN 2349-1442 , http://hdl.handle.net/10210/13004
- Description: This study evaluates the viability of pyrolysis technology as a treatment process for waste tyres with the aim of producing alternative fuel and other high value products. A financial model was formulated to evaluate the economic feasibility of this technology as an alternative disposal method. It was discovered that pyrolysis technology becomes more viable when there is guaranteed product off-takes at a given price. Further processing of the crude tyre oil and carbon black is important for production of consistent quality products. Gauteng province alone will require a capital injection of US $59.8 million to setup 14 waste tyres pyrolysis treatment facilities to treat 134,922 tons per annum of waste tyres with a potential investment return and gross margin of 29.79% and 34.59%, respectively. These facilities can produce up to 46.8 million litres per annum of refined tyre derived fuel at cost of $ 0.516/litre and other secondary value add products for local and export markets.
- Full Text:
Characterizing the effect of processing parameters on the porosity of laser deposited titanium alloy powder
- Mahamood, Rasheedat M., Akinlabi, Esther Titilayo, Shukla, Mukul, Pityana, Sisa
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2014
- Subjects: Laser metal deposition , Medical implants , Porosity , Processing parameters , Titanium alloy
- Type: Article
- Identifier: uj:4739 , ISSN 2078-0966 , http://hdl.handle.net/10210/11725
- Description: Laser Metal Deposition (LMD) is an additive manufacturing technique that produces parts layer by layer directly from the Computer Aided Design (CAD) file. Highly customized parts with complex shapes such as medical implants can well be manufactured using the LMD process. LMD has been used to produce a wide range of patient specific (customized) parts. Porous parts are of particular importance as medical implants because they can potentially aid the healing process and proper integration of the implant with the body tissues. In this research porous samples of titanium alloy (Ti6Al4V) were produced using the LMD process. Spherical shaped Ti6Al4V powder of particle size ranging between 150 to 200 μm was used. The effect of laser power and scanning speed on the shape, size and degree of porosity of the deposited tracks was investigated. The results showed that as the laser power was increased and the scanning speed decreased, the degree of porosity was reduced. The size of the porosity was also found to reduce as the laser power was increased.
- Full Text:
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2014
- Subjects: Laser metal deposition , Medical implants , Porosity , Processing parameters , Titanium alloy
- Type: Article
- Identifier: uj:4739 , ISSN 2078-0966 , http://hdl.handle.net/10210/11725
- Description: Laser Metal Deposition (LMD) is an additive manufacturing technique that produces parts layer by layer directly from the Computer Aided Design (CAD) file. Highly customized parts with complex shapes such as medical implants can well be manufactured using the LMD process. LMD has been used to produce a wide range of patient specific (customized) parts. Porous parts are of particular importance as medical implants because they can potentially aid the healing process and proper integration of the implant with the body tissues. In this research porous samples of titanium alloy (Ti6Al4V) were produced using the LMD process. Spherical shaped Ti6Al4V powder of particle size ranging between 150 to 200 μm was used. The effect of laser power and scanning speed on the shape, size and degree of porosity of the deposited tracks was investigated. The results showed that as the laser power was increased and the scanning speed decreased, the degree of porosity was reduced. The size of the porosity was also found to reduce as the laser power was increased.
- Full Text:
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